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1.
Environ Sci Pollut Res Int ; 29(13): 18891-18904, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34705201

RESUMO

This research examines how financial transformative power sector reforms affect energy efficiency and the economy in a sample of economies from South Asia, the Middle East, and Europe. We applied two stages of OLS, Bayesian VAR, and Data Envelopment Analysis (DEA) methods to a panel data set from 1995 to 2018. According to empirical findings, institutional deficiency has a negative effect on electricity reforms, implying that the greater the impact of reforms on electricity performance, the higher the institutional efficiency, A collection of reform initiatives involving a variety of reform agencies will boost energy efficiency by up to 13% and per capita electricity access by 62%. Despite recent reforms and regulatory measures, the electricity sector continues to face challenges in terms of private investment and structural flaws such as energy inefficiency, significant technological and financial losses, low power quality, and outdated transmission and network infrastructure. Interestingly 13.2% increases can be found in energy efficiency after electricity reforms. Unlike previous studies, our findings reveal a conflict between the broader economic effects and the welfare impact on electricity consumers.


Assuntos
Conservação de Recursos Energéticos , Teorema de Bayes , Conservação de Recursos Energéticos/economia , Europa (Continente)
2.
Materials (Basel) ; 16(1)2022 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-36614512

RESUMO

The performance of water as a heat transfer medium in numerous applications is limited by its effective thermal conductivity. To improve the thermal conductivity of water, herein, we report the development and thermophysical characterization of novel metal-metal-oxide-carbon-based ternary-hybrid nanoparticles (THNp) GO-TiO2-Ag and rGO-TiO2-Ag. The results indicate that the graphene oxide- and reduced graphene oxide-based ternary-hybrid nanoparticles dispersed in water enhance the base fluid (H2O) thermal conductivity by 66% and 83%, respectively, even at very low concentrations. Mechanisms contributing to this significant enhancement are discussed. The experimental thermal conductivity is plotted against the existing empirical hybrid thermal conductivity correlations. We found that those correlations are not suitable for the metal-metal-oxide-carbon combinations, calling for new thermal conductivity models. Furthermore, the rheological measurements of the nanofluids display non-Newtonian behavior, and the viscosity reduces with the increase in temperature. Such behavior is possibly due to the non-uniform shapes of the ternary-hybrid nanoparticles.

3.
Materials (Basel) ; 15(1)2021 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-35009170

RESUMO

This study presents the rheological behavior of water-based GO-TiO2-Ag and rGO-TiO2-Ag ternary-hybrid nanofluids. The impact of nanoparticles' volumetric concentration and temperature on the rheological properties were studied. All experiments were performed under temperatures ranging from 25 to 50 °C in the solid volume concentration range of 0.5-0.00005%. The data optimization technique was adopted using the Taguchi method. The types of nanomaterials, concentration, temperature, and shear rate were chosen to optimize the viscosity and shear stress. The effect of shear stress, angular sweep, frequency sweep, and damping factor ratio is plotted. The experimental results demonstrated that the rheological properties of the ternary hybrid nanofluid depend on the ternary hybrid nanofluid's temperature. The viscosity of ternary hybrid nanofluids (THNf) change by 40% for GO-TiO2-Ag and 33% for rGO-TiO2-Ag when temperature and shear rates are increased. All the ternary hybrid nanofluids demonstrated non-Newtonian behavior at lower concentrations and higher shear stress, suggesting a potential influence of nanoparticle aggregation on the viscosity. The dynamic viscosity of ternary hybrid nanofluid increased with enhancing solid particles' volume concentration and temperature.

4.
Pathogens ; 9(10)2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33036480

RESUMO

Acanthamoeba are widely distributed in the environment and are known to cause blinding keratitis and brain infections with greater than 90% mortality rate. Currently, polymerase chain reaction (PCR) is a highly sensitive and promising technique in Acanthamoeba detection. Remarkably, the rate of heating-cooling and convective heat transfer of the PCR tube is limited by low thermal conductivity of the reagents mixture. The addition of nanoparticles to the reaction has been an interesting approach that could augment the thermal conductivity of the mixture and subsequently enhance heat transfer through the PCR tube. Here, we have developed hexagonal boron nitride (hBN) nanoparticle-based PCR assay for the rapid detection of Acanthamoeba to amplify DNA from low amoeba cell density. As low as 1 × 10-4 wt % was determined as the optimum concentration of hBN nanoparticles, which increased Acanthamoeba DNA yield up to ~16%. Further, it was able to reduce PCR temperature that led to a ~2.0-fold increase in Acanthamoeba DNA yield at an improved PCR specificity at 46.2 °C low annealing temperature. hBN nanoparticles further reduced standard PCR step time by 10 min and cycles by eight; thus, enhancing Acanthamoeba detection rapidly. Enhancement of Acanthamoeba PCR DNA yield is possibly due to the high adsorption affinity of hBN nanoparticles to purine (Guanine-G) due to the higher thermal conductivity achieved in the PCR mixture due to the addition of hBN. Although further research is needed to demonstrate these findings in clinical application, we propose that the interfacial layers, Brownian motion, and percolation network contribute to the enhanced thermal conductivity effect.

5.
J Clean Prod ; 273: 122834, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32834565

RESUMO

COVID'19 pandemic has devastated several industries and solar energy is no exception. In its economic relief package, Malaysia has announced approximately US$ 2.9 billion in expenditure for the installation of new grids, LED street lights and rooftop solar panels. The Government will also open the tender for a 1400 MW solar power project in the year 2020, which is expected to generate 5 billion ringgit (US$1.1 billion) in investments. As these measures are intended to sustain the existing growth of solar energy potential in the country, it is vital to assess its status quo. Hence, this paper aims to review the current status of renewable energy in Malaysia as well as the initiatives taken before the pandemic to promote solar photovoltaic (PV) technology to meet the energy demands through the low-carbon pathway.

6.
Parasitol Res ; 117(6): 1801-1811, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29675682

RESUMO

Brain-eating amoebae (Acanthamoeba spp., Balamuthia mandrillaris, Naegleria fowleri) have gained increasing attention owing to their capacity to produce severe human and animal infections involving the brain. Early detection is a pre-requisite in successful prognosis. Here, we developed a nanoPCR assay for the rapid detection of brain-eating amoebae using various nanoparticles. Graphene oxide, copper and alumina nanoparticles used in this study were characterized using Raman spectroscopy measurements through excitation with a He-Ne laser, while powder X-ray diffraction patterns were taken on a PANanalytical, X'Pert HighScore diffractometer and the morphology of the materials was confirmed using high-resolution transmission electron microscopy (HRTEM). Using nanoparticle-assisted PCR, the results revealed that graphene oxide, copper oxide and alumina nanoparticles significantly enhanced PCR efficiency in the detection of pathogenic free-living amoebae using genus-specific probes. The optimal concentration of graphene oxide, copper oxide and alumina nanoparticles for Acanthamoeba spp. was determined at 0.4, 0.04 and 0.4 µg per mL respectively. For B. mandrillaris, the optimal concentration was determined at 0.4 µg per mL for graphene oxide, copper oxide and alumina nanoparticles, and for Naegleria, the optimal concentration was 0.04, 4.0 and 0.04 µg per mL respectively. Moreover, combinations of these nanoparticles proved to further enhance PCR efficiency. The addition of metal oxide nanoparticles leads to excellent surface effect, while thermal conductivity property of the nanoparticles enhances PCR productivity. These findings suggest that nanoPCR assay has tremendous potential in the clinical diagnosis of parasitic infections as well as for studying epidemiology and pathology and environmental monitoring of other microbes.


Assuntos
Acanthamoeba/genética , Óxido de Alumínio/química , Balamuthia mandrillaris/genética , Cobre/química , Grafite/química , Nanopartículas Metálicas/química , Naegleria fowleri/genética , Reação em Cadeia da Polimerase/métodos , Acanthamoeba/isolamento & purificação , Animais , Balamuthia mandrillaris/isolamento & purificação , Bioensaio , Encéfalo/parasitologia , Linhagem Celular Tumoral , Diagnóstico Precoce , Células HeLa , Humanos , Naegleria fowleri/isolamento & purificação , Infecções por Protozoários/diagnóstico , Infecções por Protozoários/parasitologia
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